Hemidactylus gramineus, Ching & Tay & Brown & Mohareb & Sethi & Annamalai, 2023

Ching, Ann Hui, Tay, Tricia, Brown, Bryan, Mohareb, Amir M, Sethi, Aisha & Annamalai, Aniyizhai, 2021, Dermatologic conditions of adult refugees following resettlement in the United States, 2015 to 2018., Journal of Herpetology 7 (7), pp. 105-111 : 105-111

publication ID	https://doi.org/ 10.1670/20-094
DOI	https://doi.org/10.5281/zenodo.7887481
persistent identifier	https://treatment.plazi.org/id/039D4957-4E2E-B05B-A9A4-FA3ACA4021CA
treatment provided by	Diego
scientific name	Hemidactylus gramineus
status	sp. nov.

Treatment

Hemidactylus gramineus sp. nov.

Figures 1 View FIG , 2 View FIG ; Table 1

urn:lsid:zoobank.org:act:8C27856D-9BAD-4880-930F-2503794734C3

Hemidactylus cf. nzingae: Ceríaco et al. (2020a: 14)

Hemidactylus sp. : Ceríaco et al. (2020a: 19)

Holotype.— UTEP 22208 View Materials (field number ELI 1645; Figs. 1 View FIG , 2 View FIG ), adult male collected near bank of Lumene River , Bombo-Lumene Reserve (-4.42027 °, 16.04687 °, 548 m), Kinshasa Province, DRC, collected by Chifundera Kusamba and Wandege M. Muninga on 7 June 2013.

Paratype.— UTEP 22209 View Materials (field number ELI 1674), adult male collected in Bombo-Lumene Reserve (-4.41843 °, 16.04420 °, 555 m), Kinshasa Province, Democratic Republic of the Congo, collected by Chifundera Kusamba, Wandege M. Muninga, Mwenebatu M. Aristote, and Eli Greenbaum on 7 June 2013 .

Diagnosis.—A small-sized Hemidactylus , maximum SVL 39.5 mm, with a short, blunt snout ( Fig. 1 View FIG ). Dorsal pholidosis heterogeneous, with 12–14 irregularly arranged longitudinal rows of subtrihedral, striated, strongly keeled tubercles at midbody. Two well-developed pairs of postmentals, the inner pair longer than the outer pair, about half the size of the mental, and in contact behind the mental. Ventrolateral folds distinct, 23– 25 scale rows across midventer. Five divided scansors beneath first digit of both manus and pes, seven beneath fourth digit of manus, seven beneath the fourth digit of pes. Males with a continuous series of eight precloacal pores. Body dorsum grayish brown, bordered by irregular, squiggly, dark brown markings that are interrupted by pairs of light gray spots, bordered by a cream/tan band that passes from the tip of the snout through the eye to the upper portion of the flanks and onto the tail, with numerous whitish tubercles on the flanks.

Description of Holotype.—The holotype is an adult male in good condition ( Fig. 1 View FIG ). The body shape is somewhat dorsoventrally flattened. Measurements and meristic characters of the holotype are presented in Table 1. Head large (HL/SVL 0.30 mm), wide (HW/HL 0.60 mm), not depressed (HH/HL 0.38 mm), distinct from neck. Canthus rostralis moderately distinct. Snout short (SE/HL 0.43 mm), longer than eye diameter; scales on snout, canthus rostralis, forehead and between eyes heterogeneous, juxtaposed, and weakly pointed; scales on snout, canthus rostralis and forehead twice the size of those on the occipital and interorbital regions. Eye small (ED/HL 0.18 mm), supraciliaries large, pointed, with those at the anterior end of orbit slightly larger. Ear opening oval (greatest diameter 0.7 mm); eyeto-ear distance greater than diameter of eye. Rostral wider than deep; three internasals, with the two outer ones enlarged and separated from each other by the smaller one in the middle; one supranasal on each side that is smaller than internasal, one pair of still smaller postnasals; rostral in contact with nostril, supralabial I, supranasal and internasal; nostrils small (> 1 mm), oval, each surrounded by supranasal, rostral, supralabial I and postnasal; one or two rows of scales separate orbit from supralabials. Mental triangular; two postmentals, smaller than the mental and in extensive contact with each other behind mental; outer pair about one third the size of the inner pair, separated from each other by inner pair and four gular scales. Inner postmental bordered by mental, infralabial I, outer postmental and two gular scales; outer postmental bordered by infralabials I and II, inner postmental, three to four small gular scales of which the outer one is enlarged and continue as a single row of enlarged scales below infralabials. Infralabials bordered by a double row of enlarged scales. Supralabials and infralabials to angle of jaw 10 (right and left) and 9 (right and left), respectively. Body relatively stout, moderately elongate (TRL/SVL 0.42 mm), ventrolateral folds without denticulate scales. Dorsal pholidosis heterogeneous, comprising conical, granular, striated scales intermixed with enlarged, fairly regularly arranged, longitudinal rows of 14 subtrihedral, strongly keeled, striated tubercles at midbody, extending from occipital region to tail, each enlarged tubercle roughly six to eight times longer than adjacent granules, surrounded by rosette of 10–12 small granules, 2 or 3 granules between two adjacent enlarged tubercles; enlarged tubercles on nape and shoulder small and pointed, those on occipital region heterogeneous. Ventral scales larger than dorsal, smooth, imbricate; midbody scale rows across belly 25 (between ventrolateral folds); gular region with still smaller, subimbricate scales, those on lateral aspect of neck granular, anterior gular scales slightly larger than the rest. Eight precloacal pores. Scales on the palm and sole smooth, imbricate, rounded; scales on dorsal aspect of upper arm larger than granules on dorsum, subimbricate and striated, dorsal aspect of forearm with smaller, striated, conical and granular scales, intermixed with a few enlarged conical tubercles; those on dorsal part of thigh and shank conical, granular, striated, intermixed with enlarged, striated, subtrihedral tubercles, which are numerous on shank compared with anterior aspect of thigh; posterior aspect of thigh lacks enlarged tubercles.

Forelimbs and hind limbs relatively short, stout; forearm short (FL/SVL 0.14 mm); tibia short (CL/SVL 0.16 mm); digits moderately short, strongly clawed; all digits of manus and digits I–IV of pes indistinctly webbed; terminal phalanx of all digits curved, arising angularly from distal portion of expanded lamellar pad, half or more than half as long as associated toepad; scansors beneath each toe in straight transverse series, divided except for distal and two basal scansors on digit I and one or two distal and basal scansors in all other digits that are single; scansors from proximal-most part of the toe at least twice diameter of palmar scales to distal-most single scansor: 5-6-6-7-7 (right manus), 5-8-7-7-6 (right pes). Relative length of digits: III = IV> V> II> I (right manus); IV> III> V> II> I (right pes). The tail bears spinose tubercles dorsally, and subimbricate subcaudal scales, about one fourth of the width of the tail.

Coloration (in Life and PreserƲatiƲe).—Vertebral region of dorsum grayish brown, bordered by irregular, squiggly, dark brown markings that are interrupted by pairs of light gray spots; the dark brown markings transition to chevrons on the tail. Crown of head with scattered, poorly defined brown markings that resemble irregular chevrons. A cream/tan band passes from the tip of the snout through the eye to the upper portion of the flanks and onto the tail, with numerous whitish tubercles on the flanks. The lower portion of the flanks has a grayish brown band that is bordered by numerous light gray or whitish tubercles. The lowest margin of the flanks is light brown with irregular brown markings, and transitions to the venter. Forelimbs and hind limbs grayish brown with irregular dark brown crossbars. Venter cream; palms and soles cream. In preservative the specimens look more brownish with the pattern not so clearly delimited.

Variation.—Variation in scalation and body measurements of the paratype of Hemidactylus gramineus sp. nov. is reported in Table 1. The paratype agrees almost entirely with the holotype, although its coloration is less contrasting than that of the holotype. Coloration of a tentatively assigned third specimen (based on a photo of a live specimen) from Mayongongo village [-4.19, 14.96, 368 m a.s.l.], Pool Department, Republic of Congo ( Fig. 4 View FIG ), is nearly identical to that of the holotype ( Fig. 2 View FIG ).

Comparison aeith West and Central African Congeners.—The newly described species can be morphologically distinguished from all of its regional congeners, including those occurring in the DRC and in the areas neighboring the western DRC: Gabon, Republic of the Congo, and Angola. Hemidactylus gramineus sp. nov. may be readily distinguished from H. ituriensis and Hemidactylus coalescens Wagner, Leaché and Fujita, 2014 , by being much smaller (maximum [max] SVL 39.5 vs. 78 mm in H. coalescens and 89 mm in H. ituriensis ) and in not having the typical dorsal crossbands that characterize these two species (and the H. fasciatus group as a whole). It may be distinguished from H. angulatus Hallowell, 1854 by having only 8 precloacal pores (vs. 20–46 uninterrupted precloacal-femoral pores in males), by having a lower number of tubercle rows on the dorsum (12–14 vs. 14–25), and by having small subcaudal scales (vs. transversely enlarged).

Hemidactylus gramineus sp. nov. is readily distinguished from H. kamdemtohami Bauer and Pauwels, 2002 , and H. richardsonii ( Gray, 1845) by the lack of basal digital webbing and from H. matschiei ( Tornier, 1902) by having spiny tubercles on the dorsum and small subcaudal scales. It may be distinguished from H. steindachneri by lacking a longitudinal row of keeled tubercles on the ventrolateral border of the flanks, and from H. hecqui by not having the nostril in contact with the first supralabial, by having a relatively larger head depth (vs. flat head in H. hecqui ), lower number of tubercle rows on the dorsum (12–14 vs. 16), by having fewer rows of ventral scales (23–25 vs. 26), and a higher number of precloacal-femoral pores in males (8 vs. 6).

Hemidactylus gramineus sp. nov. can be distinguished from H. longicephalus by having a lower number of tubercle rows on the dorsum (12–14 vs. 17–18), fewer granular scales between the dorsal tubercles (1–3 vs. 3–6), and fewer rows of ventral scales (23–25 vs. 30–33). It can be distinguished from H. paiƲae by its smaller size (max SVL 39.5 vs. 68.4 mm), a lower number of granular scales between the dorsal tubercles (1–3 vs. 4–9), and a lower number of rows of ventral scales (23–25 vs. 28–34).

Hemidactylus gramineus sp. nov. may be distinguished from H. benguellensis by a much lower number of precloacal femoral pores in males (8 vs. 23–33) and fewer granular scales between the dorsal tubercles (1–3 vs. 4–9). The new species can be distinguished from H. bayonii and H. Ʋernayi by fewer granular scales between the dorsal tubercles (1–3 vs. 3–4), and fewer rows of ventral scales (23–25 vs. 28–32 in H. bayonii and 28–31 in H. Ʋernayi). Hemidactylus gramineus sp. nov. is easily distinguishable from H. mabouia by its smaller size (max SVL 39.5 vs. 67.4 mm), lower number of precloacal femoral pores in males (8 vs. 28–39), fewer granular scales between the dorsal tubercles (1–3 vs. 5–10), and lower number of rows of ventral scales (23–25 vs. 34–37).

Hemidactylus gramineus sp. nov. can be distinguished from H. muriceus sensu stricto by a higher number of tubercle rows on the dorsum (12–14 vs. 7–12) and fewer granular scales between the dorsal tubercles (1–3 vs. 5–10). The new species can be distinguished from H. pseudomuriceus by having fewer precloacal femoral pores in males (8 vs. 14–17) and fewer granular scales between the dorsal tubercles (1–3 vs. 5–10). The newly described species can be distinguished from H. echinus by its lack of two rows of scattered spiny tubercles on the ventral side of the tail (a character that differentiates H. echinus from all other known Hemidactylus ), and by being smaller (max SVL 39.5 vs. 68.0 mm). Hemidactylus gramineus sp. nov. differs from H. ansorgii by a lower number of precloacal femoral pores (8 vs. 10– 11) and a stockier body ( H. ansorgii has a slender body and narrow head with a short interorbital distance). Hemidactylus ansorgii also has a row of pointed tubercles separating the venter and the flanks, which are completely devoid of any tubercles (see figures in Tornier, 1902; Perret, 1975), whereas in H. gramineus sp. nov. this ventrolateral row of tubercles is lacking, and its tubercles extend across the flanks and dorsum.

Hemidactylus gramineus sp. nov. can be distinguished from H. nzingae by having a lower number of tubercle rows on the dorsum (12–14 vs. 16–21) and by having irregular, undulate, dark brown markings that are interrupted by pairs of dorsal light gray spots (vs. well-marked series of dark-brown continuous ‘‘W-shaped’’ transverse markings from occiput to sacrum in H. nzingae ); the new species can be distinguished from H. hannasabinae by having a lower number of tubercle rows on the dorsum (12–14 vs. 16–18), by having strongly keeled, striated tubercles at midbody (vs. smoothly keeled in H. hannasabinae ), and by being smaller (max SVL 39.5 vs. 47.4 mm).

Distribution.—The new species is confirmed from Bombo-Lumene Reserve in Kinshasa Province, southwestern DRC ( Fig. 3 View FIG ). A photo of a third specimen from Mayongongo village [-4.19, 14.96, 368 m a.s.l.], Pool Department, Republic of the Congo ( Fig. 4 View FIG ) presents a remarkable morphological resemblance with the newly described species. The specimen is deposited in the laboratory of the Institut National des Sciences Exactes et Naturelles of the Republic of Congo in Brazzaville. We tentatively assign this specimen to the new species, but it was not possible to include it in our morphological or molecular datasets, and further research on this specimen and additional material are needed to confirm the presence of the species in the Republic of the Congo.

Habitat and Natural History Notes.—The holotype was collected in the early evening while on the ground near the bank of the Lumene River. The paratype was collected in the early evening while it was crawling through grass in sandy soil near a small pond.

Bombo-Lumene Reserve is located ~ 130–150 km east of Kinshasa, in a hilly area known locally as the Bateke Plateau (name derived from the local Bateke tribal people), at an elevation of ~ 400–960 m a.s.l. ( Kayumba et al., 2015). It was originally created as a Game Reserve in 1968, but was elevated in 1976 to Natural Reserve International Union for Conservation of Nature (IUCN) category VI because of its ecological importance ( Kayumba et al., 2015). The rainy season lasts for 8 mo from mid-September to mid-May, whereas the 4-mo dry season occurs from mid-May to mid-September. The rainfalls reach an annual range from 1,600 to 1,629.7 mm, and the average annual temperature is 24.4 ° C ( Kayumba et al., 2015). Bombo-Lumene Reserve is a forest–savanna mosaic (i.e., western Congolian forest–savanna mosaic sensu Burgess et al. [2004]), with nearly all forest occurring as gallery forest adjacent to the Bombo or Lumene Rivers (Greenbaum, pers. obs.).

We encountered the new species during the dry season that typically lasts for 4 mo ( Milau et al., 2016), and we observed large brush fires during our (CK and EG) brief visit to the reserve. Other lizards encountered at the reserve included Hemidactylus mabouia (in or near human habitations), Trachylepis maculilabris Gray, 1845 ; Gerrhosaurus cf. nigrolineatus Hallowell, 1857 ; and Panaspis cabindae Bocage, 1866 ( Medina et al., 2016; Allen et al., 2019). The specimen from Republic of Congo was collected in ‘‘savannah’’ near a village (K. Jackson, pers. com. 14 January 2009).

Etymology.—The specific epithet ‘‘ gramineus ’’ refers to the grassy type of habitat from which the species was collected in the DRC and the Republic of the Congo ( Fig. 5 View FIG ) and is applied here as an adjective in the genitive singular. We propose the French common name of ‘‘Gecko de l’herbe’’ and the English common name of ‘‘grass-dwelling tropical gecko.’’